Hydrodynamic torque converters



p 11, 1956 F. E. ULLERY 2,762,197

HYDRODYNAMIC TORQUE CONVERTERS Filed July 25, 1951 5 Sheets-Sheet 1 I NV EN TOR.

Sept.

F. E. ULLERY HYDRODYNAMIC TORQUE CONVERTERS Filed July 25,. 1951 Phase Speednp. m. I000 Phase 2 T Oufpuf Shaff Speedr m. H000 i i 3; 0ufpu1'5haff Speedn im. +1000 5 Sheefs-Sheet 2 5 Sheets-Sheet 3 I? [ng/ne Speed-rpmHOOO F. E. ULLERY HYDRODYNAMIC TORQUE CONVERTERS i l 2 3 speed-rpmelooo Phase 2-1 3 '-4T- Caup/inr i 7 3 Sept. 11, 1956 Filed July 25, 1951 $2 I Ba:

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INVENTOR.

Patented Sept. 11, 1956 HYDRODYNAMIC TORQUE CONVERTERS Fred E. Ullery, Detroit, Mich. Application July 25, 1951, Serial No. 238,459 43 Claims. (CI. 60-54) This invention relates to improvements in hydrodynamic torque converters. These improvements are particularly important to provide more desirable and more effective hydrodynamic torque converters for automobiles. Accordingly, the various references and the particular exemplifications, herein, are for that respective usage. The advantages of this invention are, neither limited to the automotive field, nor confined to any particular type of power source; consequently, the references should not be construed as defining, or implying, any limitation on the scope of usage.

There are continuation-impart applications relating to inventions which are at least partially disclosed herein. Those applications are as follows: Serial No. 255,167, filed November 7, 1951; Serial No. 261,702, filed December 14, 1951; Serial No. 271,550, filed February 14, 1952; Serial No. 283,090, filed April 18, 1952; and Serial No. 286,117, filed May 5, 1952.

Also, there are other applications claiming undisclosed inventions, but using a disclosed embodiment hereof as a setting. Those applications are: Serial No. 298,560, filed July 12, 1952; and Serial No. 313,471, filed October 7, 1952.

In an automobile, a hydrodynamic torque converter diminishes the exertion of the operator and renders a pleasing smoothness of the power drive. Their increasing popularity in automotive transmissions has been inspired and compelled by these advantages, in spite of a general lowering of power transmitter effectiveness and a reduction in starting ability. Starting ability is referred to herein as the torque converter stall torque ratio.

The term power transmitter effectiveness at a particular output speed of the torque converter is' used to indicate, not only the torque converter efficiency, but also, the ratio of the engine power developed, to the maximum power ability of the engine. It means, the percentage of the maximum power ability of the engine available at the torque converter output shaft. In equation form:

Power transmitter efiectiveness, per cent, equals Engine power developedXtorque converter efliciency Engine power developed is for wide open throttle condition, and varies from the maximum power ability of the engine according to the speed restriction imposed on the engine by the torque converter. Obviously, for high power transmitter effectiveness, the torque converter must permit the engine to attain a speed in the region of its maximum power. This condition together with the efficiency at the coupling point defines the torque conversion speed range. Also, for high power transmitter effectiveness over a wide range of torque converter output speed, the engine must be permitted to operate over this output speed range, in the region of its maximum power.

equals l At and near stall, a high engine speed is unacceptable for automotive passenger car usage, but a reasonably high torque ratio is quite important. Not only is a high engine speed at stall unacceptable but a low engine speed, as well as a high torque ratio, is economically desirableeach conduces a rapid rise in efiiciency from stall.

Consequently, and in accordance with the general power-speed characteristics of automotive engines, the torque converter should have unusual input (engine) speed characteristics over the torque conversion range: from a reasonably low figure at stall, the input speed should rise rapidly to a speed in the region of maximum power, then the input speed should dwell or rise gradually to the coupling point; providing a wide range of torque conversion in which the power available is almost the maximum power of the engine. That is, the input speed curve from stall over the torque conversion range to the coupling point should have a humpbacked form. Hitherto, the input speed curves of automotive torque converters have had a general sagging disposition between stall and coupling point. This is a natural tendency as will be shown in a subsequent discussion.

Furthermore, automotive torque converters heretofore, have had an inadequate speed range of torque conversion; consequently, the available power in the torque conversion range has been appreciably less than the maximum power ability of the engine. As will be apparent in subsequent disclosures; a wide speed range of torque conversion, a high efiiciency at the coupling point, and a high torque ratio at stall, are, by the nature of the contributing influences, conflicting features. Hitherto, these features have been compromised to avoid unacceptable inadequacy of any particular feature.

To fortify the characteristics, and to partially offset deficiencies of current torque converters, various modifications and supplementary mechanisms are so commonly adopted that they are generally considered inevitable requirements for torque converters. These arrangements are usually only partially corrective and are singularly undesirable respecting: cost, weight, proportions, complexity and operating economy and pleasantness.

For torque converter drives, the engines are usually enlarged, or otherwise altered, to increase their power. Undesirably high ratio of rear axle gears has been resorted to. Lock-up clutches with hydraulic controls are used to supplant an inefiicient fluid coupling phase with a through mechanical drive. Also, some recent applications use two mechanical gear ranges with automatic controls for general driving and a third gear range for emergency purposes.

A principal object of this invention is to provide a torque converter which has a relatively low input speed at stall but through much of the torque conversion range allows the engine unusual freedom to operate in the region of high power, contributing to high eifectiveness as a power transmitter.

Another important object is to provide a torque converter which has a high torque ratio at stall, at wide speed range of torque conversion, and high efiiciency, further contributing to high effectiveness as a power transmitter.

A comprehensive object is to provide an automotive torque converter which is unusually effective as a power transmitter, and thus is more adequate, pleasant, and economical in operation than has been attained heretofore.

These objects as well as others will be apparent in the description and in the discussion.

In the accompanying drawings, forming a part of this specification:

Figure 1 is somewhat more than a half section longitudinally through the axis of rotation of the preferred embodiment; a

Figure 2 is an enlarged fragmentary section on line tweeter ,3 2-2 of Figure 1, showing the arrangement of the oneway devices positioned in'the core cavity;

Figure 3 is an enlarged' fargmentary section on line .33. of Figure 1, showingthe arrangementiof the. one- "Way 'devices positioned between the ffluid recirculating ,pa'th'an'd theazgis of rotation;

' '.'Figure- 415 a diagram'illustrative of the ,efiiciency and torque ratio characteristics ofQthe preferred embodiment illustrated injljigure 1;

fFigurefS is adiagram illustrativeofsthe. rotativespeeds .Of, the respective, bladed members of the preferred emb ms f i ustra d, iniE u e Figure 6 is a ,diagramillustratiue of the, rate ,oi, fluid ir 1at in r th pre er ed em odimen il ust ate i 'i' i li i u 7 i a gdiasramti lustrat v .e ;=th mss,,h

of the preferred. embodiment "illustrated, in Figure .1;

ti lvil ust e iveid j shq bea' lless s a he of t l de member tpump ifi s ithi urb n ffir ls tflrise v "stator -,er the embodiment illustrated; in Fi u e 1;

i ur F1 ti I .i m-i r i t e Cha a istic's or the-preferred embodimen ijllustratedl inj Figure 1 in ,comparison with the characteristics of two well lgnown torque converters;

"16 is afdiagramf illustrative of power and specific fuel characteristics 'of' typical' automotive, engines;

*Figure 17; is a diagram illustrative of; the; power trans- 'mitting fiectiveness ofthe jpreferred embodiment fillustra-ted Figure 1, "in comparison with-.two well'fknown torque converters; '5 i i Figure -18 f is i a somewhat diagrammatic 'i1lustrationof an embodimentgwith' another'form of output drive structure, but "otherwise similar to "the preferred embodiment of Figure 1; i i i Figure 2 1-9 is a somewhat diagrammatic illustration of -au=embddiment,' with sevenbladed members as illustrated in Eigur'e '1', but with relocation of 'two of the ,one iyay devices of the stator members; a i Figure 2,0 is a; somewhat diagrammatic" illustration of an enlbodin'lent, with seven bladed members jas 1 illus- 'trated "in =Fi gure 1, but with the first an'd -second stator ember fiq ieins Figure 21 isa somewhat diagrammatic illustration of an emhodiment withsix bladed members;

Figure" 22 is aasom iwhatdiagrammaticillustration of an embodimenrwithF five bladedmembera: and,

'fFigure 2 3 is asomewhat diagrammaticillustration of an-mbddiment with four bladed members.

.llt li i le vm mlogy a ebar relat nship Before describing the specific details of 'this'einvention,

establish some of the ba'sic relationships-Which influence the 1 unique characteristics obtained,';thereby rendering -the specifica tion more -significs ant andexpressive 'of intention andpurpose and -reducingperiodic explanations.

Except as noted, terms used herein area's-recommended and with the meaning as defined per Hydrodynamic Drive Termino1ogy; pages 738-140 of the# 195 1" :S. E.:Handbook; published bycthe Society of Automotive Engineers, --Inc. Where-"optional terms are -1isted,"= the afir'stis considered preferable and Will be useddnthis specification. As used =in this specification, Fa hydrodynamicatorque converter is. aid-rive that-transmits power by dynamic fluidr action 'in a aclosed :recirculating ypath io'f toroidal form, and has a fluid coupling phase as well as torque conversion .phases .zofaoperation, and 'physically;:oom-

prises: a plurality of co akial rnembers:including ati'least, one 'pump, :twolaturbines andione :statonvwith; mountings to maintain axial spaced relationship, and torperrniteaeh 'member -to rotateforwardly about "the common ajris in I at leasLone' phase o operation; a fluidesystem including an adequate fluid supply and suitable fluid=con o l, -'as 4 well as a cooling means if required; and structural components including, a stationaryhousing or support structure, a rotable casing with; suitable seals, an input power connection, an output power shaft or structure, and a 5 reaction torque structure.

Each member has at least one row of circumferentially spaced blades, extendingacrossa fluid path between core and shell shroud elements, whi'ch respectively, define part of ';Q .iE? dTshelll b l l afiifific tthefiuidz'mf ml l path. Obviously, if desired for some members, one of the shroud elements' could be omitted the blades being projected ifrom and, supported by one ,shrondelement, and the fluid path boundary functionof the omitted element provided ineanother imanner; Each member is externally associated in accordance with its specific character, being joined by a respective attaching construction to the proper driving, driven, or reaction structure: a pump 9, .e ab ia l t contrib t -10mm at 1 r 11d direction to ,,the,output pjwermshaft;Gian ,.-a

, stator member is ioinedito a reaction structureassociated wi ,thest tienar h us ne euablinait-t transm tte gue to 'the tstationaryhouiiugat least inthe backwardfiirection. .Theattad n wnsttuctiq fi mQ ber is.. em an 'of joining the'member,to,,,and is partgofl its .,particular .s btit e A ea .reacticm, ttuct iitm ybe a Inae surfa qni nct g .rel menteon erie -pie malts 'iau ii .m yi blu ealdeviqe. r nd r ng th pa icular. menliorward rqtation is the, direction,. of rotation lof the member. All vector quantitiesin' the forward "direction are consideredpo'sitivc,. and in the backward d r tiqn neseiit u u fers. togthelflui c rcu fiug nat Th ,auera ge radius joffthe, ,fluid circuit is the, average; of the lil'e sest ds r -ed l a themal e t .de is lradiuw thefluid circuit. In reference to the'flui'd circuitfthe i an outermember ha th des gnradiifof des 5 largereand an in enmember; has ,the I design ra'dii ofjits flrlzidessmfller than the averege radius of j the fluid circuit. Rate-of'circulatiorr isfthe volume of, fluid per unit time -pas'sing a particularl location, andvherein is c ipl'es'sed, cu ft 'per sec. Belugaclosed-1: ath,-the rate-is simultaneously constantthroughout thecircuit.

he iru1a-;ie velocity is the-component of the-fluid absolute 'VlOCl in a planepassing through 1 theaxis 6f r'otation. his velocity=is equal to the' r'a-te of--circular tion dividedby 'the areanormal} tojthe circulation velocity. Flam-circumferential=velocity of the fluid -is t-he-component df thfluid absolute yelocityin a plane perpendicular to eaaiwf'm a iep- ,TQhe term bladeiangle as used. herein refers ,to the, ef- "fective' bladeanglgbeing the; includedgngle between the fluid absolute velocityand a plane which passes through theaxis ,oirotatiomand rotates.in unisomwith; the blades. Blade angles areeonsidered positive and negative, respec- -tixe y .a-ie orwar v.1 a backwar z it umt t nt ah c m n? t rinpu snewe --,headt-,i aa le the t rossihea -l t-zequatic et'ermwth tcsabeed f -'=a a1 ower input ftglbsper sec.

nx u jsaeiafienegn where-rateof circulation is cufiftnper sec., and fiuid speeific'weightis'lbs per, cufft. The influence ofa lossjhead ,isrep at v 3 ..,t ,qorrep nd na g qs h a t a i a Loss :headgift.

It is this particular combination of these factors which permits a torque converter to have a high efliciency in the coupling phase. As shown by Fig. 6, the rate of circulation in the coupling phase is low, tending to a low circulation head loss in spite of blade configurations, and at the same time, as shown by Fig. 7, the corresponding gross head is very high; consequently, the actual loss in per cent may be quite low in the coupling phase of a torque converter.

The hydraulic losses are divided into two distinct groups; namely, circulation head losses and shock head losses. The circulation head is that required to overcome the flow resistance of the passages and coincidental turbulence in accordance with the particular rate of circulation.

The shock head losses are attendant to the circumferential velocity of the fluid. Such a loss is entailed at a blade entrance which requires a sudden change in the fluid circumferential velocity. This velocity change is termed the shock velocity. The attending shock head loss, ft. equals Constant (shock velocity, ft. per sec.)

The value of the constant may generally be considered unity. Actually, it varies with the blade entrance tip form, the blade spacing, and the angle of misalignment of the approaching fluid from the blade disposition. Also, it is generally larger for back impingement on the blades than it is for face impingement. Herein, the shock head for face impingement is called face shock head, and for back impingement, back shock head.

The curves of Figs. 4-14 incl. are based on an input torque simulating the wide open throttle torque of a particular engine. Comparable curves for partial throttle conditions may be constructed by applying the basic torque converter relationships:

Pump torque plus stator torque equals turbine torque. Speed ratioxtorque ratiox 100 equals etficiency, per cent.

At any specific speed ratio:

Pump torque and the hydraulic heads vary directly as the second power of the pump speed. Fluid circulation varies directly as the pump speed.

Hence, if the pump torque is reduced to one-fourth of its original torque and the speed ratio of the output speed to the input speed is maintained: the pump speed and that of all other members will be reduced to one-half, all members retaining their original speed ratios; the rate of fluid circulation is also reduced to one-half; and, all the torques and the hydraulic heads are reduced to onefourth of their respective original values. Thus, if the particular speed ratio exemplified was that of the coupling point, the torque conversion range would be reduced to one-half of its original speed range. This is presented to emphasize that phase changes, some of which are pertinent to this invention, concur with respective speed ratios and not according to specific output speeds.

A one-way device is the term used in this specification for a mechanism in the connecting structure of a bladed member to enable the particular member to transmit torque to its respective external association but only in a specific direction, the one-way device permitting free rotation in the opposite direction. Figs. 2 and 3 illustrate suitable one-Way devices for the embodiments of this specification. With one exception, each stator member of these embodiments is, in effect, provided with a one-way device and may transmit torque to the stationary housing in the backward direction, but, for the single exception noted, each may rotate forwardly when it would otherwise exert torque in the forward direction.

One specific turbine member in each of the embodiments illustrated in this specification has a one-way device in its connecting structure to the torque converter output shaft, enabling the member to transmit torque to the Vcr=fluid circumferential velocity,

6 ouput shaft in the forward direction and permitting relative rotation in the opposite direction when it would otherwise exert backward torque on the output shaft.

Considering the moment of momentum of the circulating fluid vectorially positive in the forward direction, and negative in the backward direction; a stator member with a one-way device can increase, but can not reduce, the moment of momentum; and a turbine member with a one-way device can reduce, but can not increase, the moment of momentum of the circulating fluid.

Actually, there is a slight influence counter to the direction of relative rotation due to friction in the one-way device and in the rotational mounting of the member, some of which may be intentional to damp rotational hunting and fluctuation of the member.

Free-whirling is the term used herein to distinctly indicate the state of free rotation of a member by virtue of a one-way device in the connecting structure of the particular member.

As previously stated, a free-whirling member does not appreciably, change the moment of momentum of the circulating fluid, and hence, free-whirling is a non-functional phase of operation for the particular member. However, a free-whirling member may have other influences which are very detrimental hydraulically, in respect to circulation and shock head losses. It is apparent that a free-whirling member adds to the circulation head loss according to the flow resistance of its bladed passages; however, this loss is not appreciable in the late phases of operation when the rate of fluid circulation is relatively low.

The most serious influence of a free-whirling member, generally, is its respective shock head loss. The nature of this loss is dependent on the form of the particular member relative to the physical environment. Fortunately, with due consideration of the pertinent factors, the shock loss may be appreciably reduced and substantially eliminated in some phases. Control of these losses is a vital factor in obtaining high efficiency to augment power transmitter effectiveness, with which this invention is objectively concerned. Hence, the derivation of the expression showing respective influences is presented. Let

A=elfective flow area, sq. ft. (area normal to circulation velocity).

R=design radius, ft.

B=blade angle.

Q=rate of circulation, cu. ft. per sec.

=density of fluid, slugs per cu. ft.

N=rotational speed, R. P. S., of free-whirling member.

ft. per sec., prior to blade entrance.

And suffixes, n and x, respectively,

and at exit. And, equate the moment of momentum prior to blade entrance to that at blade exit,

indicate at entrance,

tial velocity is inversely proportional to the radius. From Equation a,

1 Rn Q N-m (V07 tan B17) and, the fluid circumferential velocity immediately after entrance in the bladed passages, equals Rn Rn (V07 tan Bz)+Z tan Bn (c) i lifheg di fierence of this velooityfrom vcr is ithe shock w'elo'c'ity, and is loss for a particularcircumferentialrvelocity at entrance.

*Thephysicaltsignificance:is simple-"the.- absolute. velocity of thecfluid ii's directionally varied-to conform: generally to itheablade efiectivecurvature, =by theinfluence of circuxlation:=path1lareavvariatiom andfiorp by the free vortex efiect of change ofiradius.

- .=.It has':lbeenustated thatc a f ree-whirling member does snot appreciably (change 1 the-moment 0f momentum of -the circulating-fluid. i z'l his is-true concerning the total efiect, but normally, there is an intervening fluctuation.

swithztheaehange in :circumferentialwelocity' (shock veloc- 1 =':ity):-.at the \bladeentrancwthere isa correspondingchange irrithe-momentgof imomentum -which imparts an-impulse :drive-to the bla'des. As the fluid passes through -to=-the -blade exit,--ithere, is a =counterbalancingreaction driveon wthe:zblades,i:.restoring the moment -of-momentum---of= the circulating sfluid.

Gharacten'stically, the -free-whirling state of a member starts aftenan= appreciable J angle of back impingement has :ideveloped. 3 Subsequently;- -this impingement; may-actually vveer to :the face: side of: the blades by virtueofrelationships shown in Equation d. --.=iSpecific1= basic: relationships and influenceswill be dis- :closeddma subsequent discussion -of the features-of the :preferred embodiment.

rDescr p ian i J-Iheaemhodiment zofi athisw-invention illustrated in Figure lyjiS; considered the preferreditzgives physical exemplifiz aiionsto; %th6.-:baSiC' conceptstaofikthis inven'tion-and adeequately; achieveswthe; comprehensive. objective. :Also, 53. o

thoroughfiescription andiexplanation-of this: embodiment .senvessto make tithe ufeatures :and characteristics ofiithe simpler embodiments apparent with only brief specific comments.

-i1-It is' intended for this; particular automotive -app'lication, that the torque converter should be supplemented with a simple mechanical transmission at the output; shaft end. This transmission should have a -rever se'-gear-and a low ratio forward gear; the-latter,-or"unusual-condisustained-z downhill: operation requiringGabnQrmaLeQQiue -t-braking. Ehe :hydrauliesystem of this transmissionserves the torque converter with an adequate supply 'off fluid rand provides -the charging J and the replenishing 3 means transmission, as well as for the flanged reaction shaft 12 bolted thereto. This is mechanically equivalents-to the generally desirable and customary arrangement in which the reaction, shaftds secured tqaastationary portion of the supplementary transmission, and which, in efiect, serves a part th 6a9fi9n,st ru ture.

' *Th torq e conv rter .c vcrI..40. .e .1lloses theltqrque converter fluid chamber and servesas part of .thepumpdriving structure from the engine. This cover has a series of circumferentially spaced knobs ,41. LScrews through the :28 of fluid cireulation, and s tarting at Z-the 'pump entrance, are:Qthe-pummmembertSfl; the first turbiue memb'er dfl, the first staton member; 80, the second:tu'rbineume'mlaer =68; the-second stator member 86; the third stator member 5 92; and the thir d'turbinemember 74.

Theipumpmemberfi has aseries -of--blades 51 across :a fifluid path bounded byshellfi52 afid c0re 53. l' l'lie driving c dnnectiotr for--the pump -member'iis a skirt-"like element 54 near the pump exit extending from the pump shell to the torque converter cover 40 to which it is fastened with screws. Near the= pump -entrance, arid -.extending=inwardly -from thepump shell, -is-a hub element -55 to which 'is-secured azsleeve- 56 which-is journaledat 13 iri-stationary-housing -10. Thepump -shell- 'flgthe driving element 54, and the hub element 55, formppart of= the torque converter fluid' casing for this par ticular embodiment.

EThe turbinemembers are :described' in the-orderof theinphysicalconnection to."the--outputg 'shaft-fthe members being arranged structurally in series relationship from a single connectionto the output shaft.

The second. turbine member -68..'hasa.series; of blades 69 across-thefinicbpath-boundedbyshell 70 and core 7 1. Near the exit of the second turbine member, and extendsingdnwardlyafrom the-shell, isaldriven hub structure con- =sistingzsof,.=:a hubfl31 :splined to ithe output .shaft 30 and rriveteduto; a: flange aelementflz associated :with' shell 70. Ibis-elementt nralsosserves: as-arotational mounting on :raceur42. Near the entrance of ithe second turbine member -rprojeoting-outwardly, is= awrirn :elementi73.

'izlhe ifirstutur-bine memberafifl: has a: se'xies of blades 61 across the fluid path bounded by .shell 62 and cor-e 63. iAidrivenl'ski-rfilikeelement 64'exterids' fromthe shelband -mates with frim element 73-=of the second tur-bine'member. At-lthe mating junction a drivinggconnection sisprovided which con'sists ofi square head pins presseddm d'rille'd holes in element 64 and registering with 'Ir iilledmot'chesin -.l; ent ;73. :Ihe. first turbine cqre hassa; driving el ment fifisi lvusnated;i flame-22 s aun s-l e s uctur integral with the core 63.

The third turbine member 74 has a--se'ries"ofblades-75 across the fluid path bourided" by shell "7 6 and-core 77. A portion-ofthe shell isformed to retaina bearingbush- 'ing '78-whi'eh=-is journaled -by-rim* 57 protruding from the ;ppmp. mgmbelbthubw elementoss; thus=.;insurin m a ie scoucentricity ofggthegthirdsturbine :member. .v'tAuone-zway id yi sziht escribedin the. following paragraphkisimer- ,posedsbetwcenathec thind..turb iuescore -77; andzthefiriving selementfi vasst)t me }withzthcfirst.turbiuencore. :JEhis h ..ti stt rdsrotation, ofetheathirdturbine memberatrelative a! firs :i flame-member;and=.enables the-third turbine :rmcmber 51 contribute; torquethrough; its idflY611iStlZllCtllf itozth storqu conyerter- ;out ut;shaft,i;but:pnly inzthe. for- 5 wari direction. A31 ham-been :describdd; the drivensstruc- Jute: tea the third; turbinernember isza: seriesuofistructu-ral :elcmentsnincludingamen-structures ofstheizfirstzandasecond turbine members.

fiigure :2, illustratcsgonessuitable.larrangenrenteandiconetioniior sonerwayidevicez 2i). {POI :ithis' :particular isiztuai ongthe llace; 32 istheidriying element of'ithe. device.

L I h IT IaC'zQ i Serrated-en its-inner surfacesandis shrunkeon s zh thirdzgturhineicore 5'7. iThel-driuennelementtzconsists .0,f:-;tWOs annillargdiscs z.34,; between.,which,.1a plurality-ref .65 :camsfiiraresseoured in-.a radially outwardspositionrelative loathe-trace 3120 217111835. :Thesannular discs: in' turn'zarc ssctzu-red;-hyvrivets i361 to lthezdriving element 66 associated =withrithez fiISifiIUIbiIlCzLCOI'. The 'swedging rollers 37 i are surged and "zgfiidedinuwedging position nbetween thecams web of the-ieng-ine'fiy-wheel and threaded into these knobs, a Ihe racetby: amlsqsg a tuat d by pi-ing 38 provide the torque converter drivipg connection. -An-output-shaft30 transmits the ,torqueconverter output power to thesupplementarytransmission.

The bladed members,,in the ordepof arrangement of .Thestator. members taresomewhatin seriesstructurally, -and nwilli-zberld-escxzibed in order of respective physical eproximitytorthe :hollow: reaction shaft- 12.

ifllhexthirdastatorpmember 92' -hasa rowof blades 93 their bladesin lthe'fluid recirculating path in theidirection across .the'ifluidma th bounded 'by shell 94 =a1id core 95.

Associated with the shell, is an element 96 which serves as an attachment flange for a one-way device 22 interposed between the third stat-or member and the reaction shaft 12. This construction prevents backward rotation, but permits forward rotation of the third stator member relative to the reaction shaft, and enables the third stator member to transmit torque through the reaction structure to the stationary housing 1%, but only in the backward direction.

Figure 3 illustrates one suitable arrangement and construction for one-way device 22. An inner race 14, concentric with the axis of rotation, is spline connected to reaction shaft 12. A cam element 15, which is a thick wall race with a plurality of cam surfaces internally, is fastened by rivets 18 to shell flange 96. Wedging rollers 16 are urged in Wedging position, between the inner race and the cam surfaces, by springs 17.

The second stator member 86 has a series of blades 87 across the fluid path bounded by shell 88 and core 89. Interposed between the second stator member and the reaction shaft 12 are one-Way devices 23 and 24, the cam elements of which are attached with rivets 19 to flange element 90 associated with the second stator shell. The arrangement and construction of each of these one-Way devices is the same as that illustrated in Figure 3 for oneway device 22. Two are used to provide adequate capacity and for interchangeability of partsobviusly a single one-way device with adequate capacity may be used. As described, the construction prevents backward rotation but permits forward rotation of the second stator member relative to the reaction shaft, and enables the second stator member to transmit torque through the reaction structure to the stationary housing 10, but only in the backward direction.

The first stator member 80 has a series of blades 81 across the fluid path bounded by shell 82 and core 83. An element 84 associated with the core provides a connection for the one-way device 21 interposed between the first stator core 83 and the second stator core 89. The arrangement and construction of this one-way device is the same as that for one-way device 20 illustrated in Figure 2. The arrangement prevents backward rotation but permits forward rotation of the first stator member relative to the second stator member, and enables the first stator member to transmit torque through the second stator member and the reaction structure to the stationary housing 10, but only in the backward direction.

Also shown in Figure 1, is a one-way device 25 interposed between the output shaft 30 and the torque converter cover 40. The construction and arrangement is the same as'illustrated for one-way device 22 in Figure 3. This one-way device may be termed an anti-coast device. It is used to prevent forward over-run of the output shaft relative to the engine-it provides more engine braking for downhill coasting, and aids push-starting of the engine. These comments are included to complete the description of the illustration. The anti-coast device is not pertinent to this specification-its inclusion in a drive is optional, and generally complementary. .In Figures 18 to 23 inclusive, this anti-coast device is omitted.

The bladed members illustrated are formed by casting; however, they may be cast, fabricated, or otherwise made, of any suitable materials without departing from the intent of this specification.

Some of the specific requirements dominating blade angles will be disclosed in a subsequent discussion. Intrinsically, turbine member blades are curved to vectorially reduce, and stator member blades are counter curved to vectorially increase, the moment of momentum of the circulating fluid. However, this specification is not limited to any particular blade form, blade tip form, blade spacing, or necessarily to a single row of blades in any member.

Operation The basic principle of operation is typical of hydrodynamic torque converters. Mechanical energy is simultaneously transmitted to and extracted from a fluid circulating in a closed path, in which: pump blades transmit energy to the fluid; turbine blades extract energy from the fluid; and intervening stator blades react and transform the physical properties of the fluid. The objective is, increased flexibility of the torque and speed properties of the available power in accordance with the needs of the particular application-in this instance, an automotive drive. It may be noted throughout this specification that: torque ratio and speed ratio characteristics are dominated by the nature of the bladed members; and, efiiciency is dependent on specific control and blending of factors attending the hydraulic losses.

The curves shown in Figures 4-14 incl., graphically indicate the operation and characteristics of the embodiment illustrated in Figure 1. As shown in Figure 4, this embodiment has a high torque ratio at stall and a wide speed range of torque conversion. Also, the efliciency is quite high over a large portion of the torque conversion range and throughout the coupling phase of operation.

Figure 5 discloses the rotative speeds of the various members. This is particularly indicative of the mode of operation in showing the respective status of each mem ber. It may be noted that the differential speeds between the first and third turbine members, and between the first and second stator members, are relatively low-accordingly, the sliding velocities are not excessive between the elements of the one-way devices in those respective locations, in spite of acting at a relative large radius.

The rate of fluid circulation of Figure 6 has the typical trend for a torque converter with torque conversion and coupling phases of operation. To enable the members to develop high torques at stall, the rate must obviously be high; to attain high efficiency in the vicinity e t the coupling point, the rate must be low, as previously discussed.

The gross head curve of Figure 7 was previously explained. It is the gross head to which the various loss heads are relative in the determination of efiiciency.

Figures 8 to 14 incl. illustrate the shock head lossesat the entrance to the blades of the respective members. These curves help to indicate the fluid directional changes through the various phases of operationface and back shock, respectively indicating face and back impingement of the fluid on the blades.

From stall through the lst phase, the embodiment'illustrated in Figure 1, operates as a three-stage torque converter, all the members being functional in the lst phase. Most of the shock head losses are characteristically high. That of the first turbine member, Figure 9, tends to be self-compensating for all phases cumferential velocity components or" the adjoining blades vary in accordance with the rate of circulation and tend to offset the physical velocity differential of the adjacent members. As shown in the coupling phase, there is a slight back shock head at the first turbine'bl'ade entrance. When justified, a one-way device could be interposed between the first and second turbine members. In this particular embodiment, it would only function for a high speed and low torque situation. I

The 2nd phase of operation starts when the first stator member starts free-whirling in response to the increasingly high circumferential velocity of the fluid discharged from the first turbine member. Thus, in this phase, the operation is functionally that of a two-stage torque converter. The first stator member is constructed with regard to Equation daccordingly and as indicated in Figure 12, the shock head loss is reduced and becomes insignificant in the subsequent coupling phase. Comparable consideration was given to the shock head loss at the entrance to the second turbine blades, as illustrated in Figure 10. After the first stator member free-whirls, the circumferential velocity of the fluid entering the second of operation-the cirturbine member-;is-*dominated'--by "the eitit bbthe first "turbine member. Theflblade' angles of-tthese members are- -arranged=-=-with regard to tfr eesvortex law," Equation a- -dhusytheshdcbheasd' loss'at' the'secorid tnrbine' en -in the' coupling-phase.

'"The Bid -phase ot operation starteuivhemthefilrird turbine -'rnember=free=whirls. 'lri this *phase, "and. "also T in the-4th phase, the operation-is that' f" a fsingleestage "torquesconverter.

"Through0ut'thetorque conversion range which in- S. cludes-d'stto- 4th' 'phases -incl.,the fluid"is discharged to ='the* thir'd turbine member-by ithe third stator number,

the blades of which have a-strong-po8itiveexitangle. iHCHCef-ihevfillidghfiS" a forwardwircumferential velocity "which'ds' very high -at;- stalk-and decreases to -alow 'value eat the coupling point,- b'eing propor'tional"totherrate of "circulation. The variation "in thc fiuid "moment "of amornenturnis considerably *greater, being :proportion'al tcr-t-he second power of'the'rate fbf circulation.

' bladeszof the hhird turbine member'arewurved' to reduce the fluid circumferential velocity, having an appp-reciable-entranceangle'of positive characten'andfor' this pa-rticirlar design, -an-eXit anglewhich is approximat'ely zero. In the -1st and"-2ri'dphases, theblatis reducethe moment of momentum-,- the"change"being transmitted to the output-'shaft astorque. -From sttllflthisinfluence -=declines:' the blade circumferential velocityincrcases protpor'tioaaily to the increaSing-rotative speed-"of the output shaft; -and -as =previously--'mentioned; "thefcircurr'iferential velocity of thefiuid from the :thi'rdstator-exit simultanemau'sly declines. When the mement of-momentum-of the 'i-flui d leaving the third -turbine 'member 'isequa-ltothat 'ofthe fiuiddis'charged from the thirdstatoreximtl'iethird eturbine member'free-whirls, and' rotationally lags behitid themutput'shaft. In fact,-as'- illustrated'in Figure i 'its speed in the 3rd and 4th phases :declines 'in "conformity with the declining circumferential velocity of the fiuid from the thifid stator eitit; howeven-inthecouhlingjahase its speed again increases -iu responsetothe increasing circumferential -'velocityof -the fluid as then dominated thythe -secorid -tur'bine' member.

" Fhe" shock head loss at theentranee to the'third turbine memb'er is i-llustrate'd in l-" igured 1. "Iheirifluence ofits eexit design radius-islargerthan-its' entrance desigrr radius as wilbbedisclosed in the' subsequent discussion.

Figure 8 illustrates the 'sho'ckhead 'ioss atftheentrance to-' thegepump memberblades. "The r-ac'tion' of the third eturbine member is*a' *vitalfactor in curtailing the'iusual extreme" range 1 of shocle velocity at-* the pump -entrance. {Elle circumferential velocity' of the fluicl -ente'ring f'the epump member issasuccess-ively dominated? by the third turbine member .in the -1st'-'and-*-2ndphases;'"by* thefthifd estator memberin the iird and '-4th -phases;"and;by the sec- -on'd turbine member'in the *coupling plrase. "Thein'fluence of the thii d turbine *member'permits- '-a=-pu mp blade en- -trance angle oftappreciablvnegative character; Which 'is (essential to keep'thehhok headlosseslow;in. the 3rd, 4th and-coupling phases.

The 4th= phase' begins*-when-'-the secondstatornieniber thee-whirls. T-he-' shock-head loss'at the'-blade"entrance of the second stator member 'is illustratediin.Figure;l3. 'z'l he circumferential rvelocity 'off'thefluid entering this -merr'rberis dominated by the second turbinemembetfor ;.=allrphases (if-operation. "-The eirifbla'deangle 'of'thesecondi turbine member'isa largeangledfnegative character. [The :second: stator" blades are ourve'd from a 'mdiumsize tentrance angle -;:of.; negative :character to an-exit angle fiwhich -is..approximately ;zero. 'ZThBS-hOCk iheadilosses of .thisgmemberjare curtailed :bythei-influencesofzbhangetin T;

. radius indicated inrEquation pd.

. The ..coupling phase. commences; when-Aha, tl1i-rd;-.,stator memher free-whirls. :Eigurel4 illustrates,thmshockhead loss .at .the'blade irentrance pf .this, .thirdestator; member.

12 V member-is dominated by the-second stator memberiir the 1st2nd, and 3rd'phases;'and;=by the secondtrirbine anem ber-in 'the 4th, and'the-coupling phases. Thethii'd stator .blades curve from a medium size positiveangle atentrance to a-large-positive angle at exit.

'In the coupling phase-the pump-member and the fir'st =and-' second turbine members are the only members that =appreciably influence; the moment ermomentum of the circulating fluid. Actually, the first-and-second turbine members perform like a single turbine' -rnember, "receiving fluid from the pumpexitand dischargingit to the-pump entrance This invention-is not -lim'ited to the free=whirling=se- :quence described, nam'elyz the first-stator meinbenthe thii'd turbine- -memberj the a second stator =member, and :finally, the i third stator -rnember. LBy modifications :bf

blade angles, designradii-=and"ifluid" path' areas; these- -quence may: be changed: thetree whirling of the third turbine member may start earlier than thatof' the first I stator mernber; or- 'later than that ofthe-second-=stator *member; 'also,-thefirst 'andsecond stator members may sbecharacterized toindependently free whirl at, or about, the same time Discussion In a hydrodynamic torque converter, the-variousmembers act andcoact as a combination .to.achieve:.the,par- "tieular characteristics 7 of. torque .ratio,,..sped:. ratio, .tef- "fi'ciency and power transmitter, effectiveness. LTherateof circulation of the, fluidat any patticirlaroutputgpeedds :dependent on.the cumirlativeiififluences 0 ..al1. lthe 1nem- "bers; and the reactions of .the..me,ri1bers in., turnaregdependenton' therate of fluidcirculation. .Althoughapar- 'ticular member may be nori function'aljnaspecifiqphase, it usually .is an importantcontributingIfactor aiding.:thc desirable torque converter characteristics eachieved,-.in that specific .phaseeby its, action .airdlinfluenceljmother phases,jthe other members arelpermittedto havephysical features which are conducive. tonthe adesirablescharacteristics achieved in, the specifiq ,phase.

W'In'thepreceding explanationof the operationsofahe embodiment illustrated in, Eigure 1,. .Ithe avoidanceot shock'head losseswas emphasized. I'The: factfthat a,.par-

ticular reduction in shocki head loss improves. etficiency 'may'be conceded, .butthemanner in whichthis improvementiin e'fliciencylis obtained.is.rather.involved,. and. is typical of the actions and readtionslinfthisclass lohtorque converters. j Consider'lthesejinfluencesgat.a specific-outp speed. "Part of theishofckl headsavingiist allocated torchculation head to increase theratefofi circulation. .Accotd- -*ing y; p p' speed is reduc d..s viuglalhigh r spee 'ratio ,'=and accordingly, a' higherefficiency. '1f...the-,spe;: ific output speed is .1 in the torque, conversion .tr l e, lthei in- -creasedirate 'of circulation increases '.,the ;.tor.que..r' iti o, "which"also:-contributes. to a higher fiiciency. :fThgiJhysi- "c'al sizeof the-torque converteris, also, a'fie'cte'd-f therelation'ship of" the torque converter;to the. engine.-.is,maintained, the torque converter must, be, revised relative ,to "size and biade angles particilla'rlyithe blade. angle. attthe pump exit.

In the. following discussion,v-the g'iiificant .-relationships-of some of theunusual'teatures .of the yai'ioustmem- :berswill" be :disblose'd. First, (the requirements .at. st'alll and at the "coupling point will .begdisclosd; Zthen, the

internal and intervening features arid'niiifluenceswilli be revealedmndfdiscussed; arid"finally,.;the results of ,the combined influences and coactions will lbe .cemiiile'd, 1 showing relative superiority. of power transmitterljfiec- *tiveness.

KTheengineYspeed'at; and in the proximity of ,stall could be low if 'consideredioiilyfor the torque converter output -power-demancl. A iow'en'gine speed aridja high torqueratio'conduce a-rapid rise in efficiency from stall. high stall speed has a tendency to increase the torque ratio; but is an inefi'icient means of augmenting that property. ,The

@hea iqu li eren ial-t:YeIQC iY n the ihuidgenteriggi this ,;'E5..,general.aut omotive pol-ieyristo. useaaustallss-peed lhigh enough to keep within reason the creep tendency of an idling engine thus, permitting the omission of the mechanical clutch. This invention is not restricted to applications without clutches, but the stall speed of the embodiment illustrated in Figure 1 conforms to that customary automotive practice. Inasmuch as this torque converter has a higher stall torque ratio than known automotive torque converters, the stall speed selected is also slighter higher, to limit the creep to a comparable tendency.

The engine speed at the coupling point should be in the vicinity of maximum power of the engine; if appreciably below this speed, the power available in the torque conversion range will be accordingly curtailed. Generally, it appears desirable to have the coupling point just below that of maximum power-this favors torque converter efficiency and engine fuel economy. Figure 16 illustrates the average characteristics of four recent automotive engines. From these it appears that the coupling point engine speed should be approximately 30003200 R.P.M. It is not unreasonable to expect a coupling point efliciency of 92-95 per cent; hence, the coupling point output speed is 2800-3000 R.P.M., which gives a torque conversion range much greater than that of known automotive torque converters.

Previously, it was shown that the third turbine member avoids high shock losses at the pump entrance, by dominating the circumferential velocity of the fluid entering the pump in'the 1st and 2nd phases. This third turbine member has an exit design radius larger than its entrance design radius. One reason being, to avoid high shock losses at entrance to its blades when it is free-whirling. This may be shown by application of Equation d. For this demonstration, let suffixes s, sx, t, tn and ex indicate, respectively, third stator member, third stator exit, third turbine member, third turbine entrance and third turbine exit. Hence, shock velocity, equals Assume that the design radius of the third turbine member is constant, then the first half of the equation is zero, and the shock velocity is the differential of the entrance and exit blade components of circumferential velocity. Also, as previously stated, the blade exit angle is approximately zero. When the exit design radius is larger than the entrance design radius, the first half of the equation becomes significant, and reduces the shock velocity approximately by its value.

In the 3rd and 4th phases, the circumferential velocity of the fluid entering the pump member is dominated by the third stator member. To avoid high shock head losses at the pump entrance in these phases, a medium-size nega tive blade angle at the pump entrance is required.

In the coupling phase, the circumferential velocity of the fluid entering the pump member is dominated by the second turbine member. To curtail the shock head loss in this phase, it is advantageous to have the exit design radius of the second turbine member larger than the entrance design radius of the pump member. This may be made apparent by the physical conditions. Assume that these radii are equal-the rotative speed of the second turbine member is, intrinsically, lower than that of the pump member, and the second turbine exit blade angle is larger negatively, than the pump blade entrance angle; hence, the circumferential velocity of the fluid discharged from the second turbine member is appreciably lower than that after entrance in the pump blades, causing a high face shock head loss. By a larger radius at the exit of the second turbine member, the circumferential velocity of the fluid discharged is consequently increased. Also, as the fluid flows to a smaller radius at the pump entrance, the

14 circumferential velocity is further increased in accordance with the free-vortex law as expressed by Equation a.

In the preceding paragraph, it was shown desirable to have in effect a radial outward trend of the fluid passages of the third turbine member, and inasmuch as fluid is discharged directly to the pump member, the exit design radius of the third turbine member must not be larger than the pump entrance design radius. Hence, the exit design radius relationship of the second and third turbine members may be stated-the exit design radius of the second turbine member should be larger than that of the third member.

The first stator member, by virtue of its location in the outer half of the fluid recirculation path, directly improves torque ratio near stall, and indirectly permits high efli ciency in the vicinity of the coupling point, even with a wide speed range of torque conversion.

The large design radius of the first stator member enables it to develop high reaction torque with a reasonable rate of fluid circulation, but its large radius correspondingly restricts its direct functional speed range. A unique feature of this member is its form, which conforms to the relationships of Equation d, and thus avoids appreciable shock head losses in the subsequent free-whirling phases. One favorable influence of this member is indirect, but nevertheless, it is very important-it relieves the other stator members, positioned in the inner half of the fluid recirculating path, of extreme reaction torque demands near stall, for which they are physically at a disadvantage; thus, permitting these members to be featured for high efliciency in the vicinity of the coupling point. These particular features may be definitely shown by the free-whirling relationship of the third stator member to the second turbine member in the coupling phase. In an equation of the free-vortex relationship, similar to Equation a, let suflixes t, ix, .5 and sx, respectively indicate the second turbine member, second turbine exit, the third stator member and third stator exit, then it Asa;

Solve for Nt at the coupling point, where Ns=0 Q @ztan Bs:v tan Biz] 27rRi$ Rta: Asq Atx In satisfying these requirements, it is known that the rate of circulation must be reasonably low to avoid excessive circulation head loss and also to retain a high gross head. As previously stated, the blade exit angles of the second turbine member and of the third stator member are made as large as practical-the limitations being: the passage choking effect of large blade angles, and the cor,- respondingly high fluid velocity relative to blade surfaces; large shock angles at the entrances to the second stator and the third stator blades; and, objectionable warp and contortion of blades. The exit radius of the second turbine member is made as low as practical with consideration of, space requirements for the inner connecting structures and drive devices, and the shock velocity conditions to the second stator member and to the pump member. The remaining factor is that of passage areas. The influence of the first stator relieving the extreme conditions near stall, permits these areas to be unusually small, and thus promotes high efliciency in the vicinity of the coupling point.

The most novel and one of the important contributions of the third turbine member to power transmitter effectiveness, is its influence on the pump member speed curve. It is the novel influence of the third turbine member which gives the humpbacked form to the pump member speed curve in the torque conversion range as illustrated in Figure 5, and thus grants the engine unusual freedom to develop power through the torque conversion range-the pump member speed being the torque, converter input speed and equal to the engine speed.

This -unique"pump"member speed characteristic is obphasesfbut with constants difiering',"respectivelyfasithe tained'byreversing thetrend" of themoment of momentum features of' thesecond arid-*thirck turbine exits. ofthefluid enteringthe pump from stall through'the 1st "Figure l""i11ustrates"the characteristics'of the embo di- '-arid"2nd'-'phase,s; the 'fluid-is discharged to the pumpen- 'menrshown' in Figure 1,"in"comparisonfwith,"the"pubtrance-by the' thirdturbine'member-whichrotates in unison '6 li'shed characteristics of "two "well known automotive with the-output shaft; "thus; theunoment of'momeutum" of torque converters. "The"'short"dash curves; marked thfluid dis'charged-tothe-pump entrance has an' increasing are thoseof'a" torque" converter inwhi'ch thefinat's'tator "trend whichcauses the speed-of thepump-member to rise memberdominates;through' the"torque'conversion'rarlge,

unusually rapid; through the S'rdand' 4th phases, 'the'third thefiuiddischarged to thepumpmember entrance. The tu'rbine'member"is freewhirling, thefluzid'enters thepump v g dash curves, marked are 111056.501 a torque "member as dominated bythe stationary third 'statorjmemcouverterin'whiclr thefinal turbine member rotationally ber; consequently, the moment of momentum of the fluid secured tothe output shaft,-'dominatesthefluidfiisbharged dischargecl'to the pumpent-ran'ce has a dec'reasing'trend, t0 the*pumpmemberen rance. T 'e eCHrV6Si11liSti te being proportional to the second power'of the declinin the superiority 'ofithe embodiment or Figure 1 ,"regarding: rate"of""fiuid' circulation," which trend has anestr'aining the "freedom grantedfto the engine'todevelop power," the "influence on the" speed-of the Pump "member. These range efwel'qufeonvefsien,iefquvmfiltiPlieation,

reversing infiuencesand'trendsare superimposed onthe fli ien v.

gene 'altrendbf the pump member'speed to rise with the "Figure '16illustratestheiaveraged'power characteristics "declining rate'bfffiuid 'circulation,"causing. the humpefifouf feeelltalldwllkfiowlfalltomotiveengines- The "backdispeed curve. The influence of the third turbine P "P aYPeTTeflf ef'maximuml P e *member on the speed-"of'the pump? member is intensified relation P p r fuel *andhastenedby the exit :design' radius 'of the third turbine e -"p is, included; w indicatethe membei'being'larger than that of the third stator member; mesfieceflomieal fange'ef Op tw p gu equivalent to stating,- the xird Figure 17 illustratesthepower transmitter eife'ctiveness radius of'the third tunbinernember'being larger than its of the embodiment of Figure Fofeompelisonfsimilal' "entrance' design'radius. curves are included for torque converters "-Aiand' B, In" contra'stfthe input'speed" curves of, known 'automothe characteristics "-of twhich'were shown'iin'Fignre 15.

"tive'torqne-conve te -have a; gi nd -b t -All'b-f these effectiveness curvesare 'based' on the curves.

purnp 'spee'deXpressionsrnay-be" derived. Theseexpresm "'P W P Y the P T P" sions-indicate the saggingn'ature. gineysped. "This comparison'clearly shows thesuperi- 4 For a'torque converter in whichthefin'abstator'memy" e gP her -discharges'the fluid diredtly 1 01' more-pump "transmitter ffectivness. This"-improvement iyparticumembers-"in series relation ship, the pumpffspeed equam" advantageous lp 'Zone 0f I 20 -tior'1 is, M. P. H., which is a' 'torque converfer =output-speed of about 800 to 2400RFP. M. "In this zone, relative to torque Pump epeed=-+C Q converter A, theaavatilableipower is l0 to'"20 per=cent ,,greater. Also,'.in' this zonethe road load power is 10 to 30:.per4cer1t. of lthenavailableioutput power from torque --converter" A'Z Hence, thetorque converter illustrated and the passagetareasz'atthe exits ofihqparticular stator f P tog-L275: ger'lpcemfmompowfin available and pump members, aridathemump input torque; which f or, ;accelerattonuor hillz'ollmbmg'zthnn torque converter :-;in thegparticular torque: converter :environmenLwgives a {ofthfttorque"convrslograngmotque speed: curve=-extending: front-the; specific stall' speed-to :the q r somewhatlless fdeficlent TEP YF transspecific;coupling pointspeedr :FOrEatypicaL-rate fimitterreftectlvene jhant torque converter :A, =b :cula-tionzcurve; it isobvious -that there will be an appre- Phewouphngpmnt thexdeficlency fi f; t Same {mils ciable --sagging tendency of the. speed icurve fromzstallto iriszmqre i q atofique FOnYe-rter i 'i Sthe COUPHDEPOEL zmheipump {speedy 50.ldeficiencyas;chieflyvdue. toanefficlencyraslshowu1111'Ihgure figure 5:.hasethis-eformiofvequationiin :the' 3rd and-4th Tillsmeansmwered ewmmy- ;,phases,: only. :Theiconstants "of courseare .differentand ""Ozhe'r *embodi-mems givevai'flatter slope'totthe curve. rEor-=a torque 1 converterin -.which-.a turbine membeg rotates-.in unison with: the output shaft and-'t-dischal ges .thefluidi directly-,toethet-pump member, the; pump speed Where Q-.is: the rate .of tfluidscirculation, and C1: andCz are constants according to: the radii, the blade angles,

7 It: has-.beemshown that, for a particulate-power :source, the-humpbackedform ofuinput speed-curve increases the torque convertervoutput power inthertorque conversion range, 'JIhe :embodiment illustrated by Figure 1. is. only i. on'eecombination of bladed members which may-consti- C 7 a tute aetorque 'conver-ter. IThere are other combinations of sl um-pispee +-G1Ni+ aQ rbladed-flmembers which have. specific rutility, and for il which,..this humtabackedinputspeed curve will bevery -v'vher'e'"'Nt is'the turbine speed arldICa,'.'C4,. andICsaIe r'adyamggeous- Subsequently constants according to: the. radii,'fthe"bladefangles, arid a a passage areas at" the exits of "the particular turbine and P eY q l e i m m eQW pump. members, and the pump input torque; which, in "ese w emamecl-byiumquely fi e P than-5nd the particular torque converter environment, ,gives aspeed momenwf f' 'fluld-dlschatgedto curve extending from'the specific stall speed to the specific "eR me e w to'itheimfiuence oi E W coupling point speed. f'ltl'istapparent thati'there w'illlbe e me b 4- s q a sagging tendency of the input-speed curve from. st-all t0 e l eie e W F ;FP ??Ea-P "'thecou'filing poinfl'thou'gh somewhat 1685mm thatoflthe 7o l h EE I E Whi e b y f w "prec ding equation, 'i h pump dm "i m 113112701 :;co1lect1ve ly,..;forward1y firm, L but ebackwa dly "'Eigure'S has this' form at equation in lthe' lst lan'd'i'2r'1d .v le, renderin :ftheuntem member; ab jphasesfbut'the 'constantsaredifierent to perrr'iit asrapid t0 fil y e r but? inefieefive i0 fi Y' D' rise'of'the input speed. The equation of. the curvel-in'the creasefthc'momefi 'f'mmfienturnf the"circ 1 oupling phase is siniilar to"-"*thatfor' the"1stafid2nd"75"'Thereare"many arrangementsfor'rende'ringatorque'cou- 17 verter member one-way acting, as well as many known types of one-way devices. Also, there are numerous devices which, with or without supplementary control, simulate the influence of a one-way device. Just to emphasize the multiplicity and diversity of such devices, without trying to be all-inclusive, some will be mentioned.

In the class of one-way devices are arrangements employing: pawls, ratchets, wedging elements, toggles, sprags, or wrapping elements.

There are numerous types of clutches which may be actuated by a controlled power mediumsuch as, hydraulic, mechanical, vacuurnatic, pneumatic and electrical. If the regulator is speed ratio conscious, the clutch influence will be equivalent to that of a one-way device. Also, if the regulator responded to torque reversal and to relative speed reversal beween the clutch opposing elements, respectively, to release, and to apply, the influence would be equivalent to that of a one way device. Another equivalent regulator would be that with a signal vane radially pivoted on the interposed turbine member ahead of the blade entrance, to signal the regulator to release, or to apply, the clutch, according to the angle of incidence of the approaching fluid relative to the member.

If the clutch is basically speed responsive, the release of the third turbine member will tend to be early for high input torques, and late for low torques. This tends to increase the shock head losses for the extreme torques; however, for some applications, there is some merit in an early release for high input torquesit permits a higher engine speed and more engine power earlier in the torque conversion range. Consequently, for this usage, a speedresponsive clutch may be considered a practical simulation of a one-way device. The clutch may be centrifugal acting by design, or separately controlled by a speed responsive regulator, with or without, supplementary infiuence of engine manifold pressure, and/ or throttle position.

The interposed turbine member may be one-way acting by virtue of its blades being, individually, forwardly firm, but backwardly yieldable. Each blade may be hinged with a suitable forward stop. The hinge axes may be substantially radial near the blade entrances with one or more rows of blades as disclosed by Dodge Patent 1,959,- 349, and by Coats Patent 1,760,397; or, the hinge axes may be substantially parallel and adjacent to the shrouds, as indicated by Teagno Patent 2,376,462.

This interposed turbine member could be a retractile member. Physically, this would involve a reshaping of the fluid recirculating path and providing the interposed turbine member with passages having more radial trend. The member would be retracted axially from the fluid path when its blades tended to increase the forward moment of momentum of the circulating fluid. There are many forms of retractile members and retracting mechanisms. Some early forms of retractile members are disclosed by Fottinger Patent 1,199,361. Helically retractile members are disclosed by Jandasek Patent 2,326,655 and Lysholm Patent 2,292,384.

Some combinations of bladed members, and some variations of connecting structures between members and their related external components, are somewhat diagrammatically illustrated in Figures 1823 incl. In the description of these embodiments, the principal members are mentioned, and the distinctive features, as well as the specific utility, are explained; but to avoid unnecessary repetition, a reasonable degree of reliance is placed on the embodiment illustrated in Figure 1, which was described and explained in detail. Comparable members, elements, and components are numbered with the same tenths and unitary digits used in Figure 1, but preluded with a particular hundredths digit. Members are considered comparable according to similarity of influence and function, rather than similarity of name; that is, if a particular first turbine member is most comparable to the second turbine member in Figure 1, its reference numbers have the respective tenths and unitary digits of the second turbine member in Figure 1.

Figure 18 illustrates another form of drive structure from the third turbine member 174 to the torque converter output shaft 130. The reaction shaft 112 is extended and fastened to the stationary housing 110 by adapter 107. The combination of bladed members is the same as illustrated in Figure 1.

This particular drive structure from the third turbine member to the output shaft includes two gear sets and a countershaft 1&4 rotationally mounted in the stationary housing structure. The shell 176 of the third turbine member 174 has an inwardly extending element 179 socured to a flanged sleeve 101 rotationally free in the pump hub sleeve 156. The outer end of this flanged sleeve is secured to gear 1132 which drives a gear 103 rotationally free on countershaft 104. The other end of this countershaft is secured to gear 105 which meshes with gear 106 mounted on, and secured to, the output shaft 130. Interposed between gear 103 and the countershaft 104, a. one-way device 120, which permits the third turbine member to rotate forwardly at a speed slower but not higher than a specific ratio of the output shaft speedthe specific ratio being the total ratio of the gearing.

One advantage of this arrangement is that the speed range and the intensity of the influence of the third turbine member may be easily varied by selection of gearing most desirable for the particular application. If the gearing ratio permits the third turbine member to rotate forwardly faster than the output shaft, the effect, relative to unisonant rotation, is a more rapid increase of the pump member speed, but over a shorter range of output shaft speed. Also, there is an increase in the output shaft torque-the increase being equal to the housing reaction torque attending the specific gearing. Contratrends, of course, are obtained when the gearing ratio restricts the third turbine member to a forward speed slower than that of the output shaft. if desired, optional ratios may be provided by selective gearings; or, a variable ratio may be obtained by using planetary gearing with the third branch of the gearing rotationally influenced by another component, such as the pump member.

Another advantage is that the physical environment of this arrangement permits the use of a smaller one-way device than that of the embodiment of Figure 1; also, the location is more accessible for the use and control of a simulating device.

A novel arrangement may be incorporated in the drive structure of the third turbine member for reducing vehicle creep. Actually, this may also be provided in the structure of Figure 1, but the accessibility of the drive structure of Figure 18 tends to make it more favorable. This creep reduction may be obtained by merely releasing, rotationally, the third turbine member when the vehicle is stopped with the engine idling. For the characteristics of Figure 1, and normal idling speeds, this would reduce the pump member torque, hence the creep torque, to approximately one half. Some of this reduction could be sacrificed to allow a lower design stall speed. The arrangement would functionally consist of a small clutch in series drive relationship with the one-way device 120, the clutch being controlled by a speed responsive regulator associated with the engine, or possibly by throttle position or manifold pressure. For the sake of simplicity, the one-way device could be omitted, the clutch serving both functions with speed responsive regulation, with or without, supplementary influences previously mentioned.

The general arrangement in Figure 18 may be in line with the trend. Serious consideration has been given to the use of drop gearing, to lower the transmission and the vehicle drive shaft relative to the floor structure. For this arrangement, the countershaft 104 would be the input shaft to the transmission.

The embodiment in Figure 19 has the same combination of bladed members and the same torque converter 19 characteristics as that in Figure ,1. The differences are those of structural connections, the utility of each depend ing'on the nature of the application environment.

In this embodiment, part of the reaction structure of the first stator member 280 is a one-way device 22 1 interposed between the first stator core 283 and the third stator core 295, preventing backward, but permitting forward rotation .of the first stator member 280 relative to the third stator member 292. This arrangement tends to be advantageous for use with heavy duty engines, having medium or low operating speeds. The principal advantage is. a matter of balancing thrust forces of the first and the third stator membersnear stall, the first and second stator members exert large reaction forces, axially, toward the engine, but that of the third stator member is in the opposite direction. Also, the third stator member, by virtue of its large blade angles, tendsto be torsionally stronger than the second stator member, and hence, more suitable for transmitting the reaction torque of the first stator member to the reaction shaft. Torque requirements being reduced, the second stator member 286 has a single one-way device 223 in this arrangement. The major disadvantage is that, the rotational speed difierential between the first and third stator members is larger thanbetween the first and second stator members, as shown in Figure 5; however, for use with a lower speed engine, this speed ditierential will be likewise reduced, retaining reasonable sliding velocities between the elements of one-way device 221.

Another departure in the structure of Figure 19 from that of Figure 1, is that the one-way device for the third stator member is located at the outer end of the reaction shaft; being, a one-way device 222 interposed between the stationary housing 210 and the reaction shaft 212. At the inner end, the third stator member is rotationally secured to the reaction shaft-from the third stator shell 294, a hub element 296 is secured by key 297 to race 214 which is splined to reaction shaft 212. :This construction permits the use of a one-way device which inherently has physical proportions inconsistent with the confined space inside the torque converter. Also, this reaction shaft rotates with the third stator member in the coupling phase; thus, reducing the sliding velocity of the second stator elements and the thrust sliding velocity between the thrust andretaining surfaces, respectively, of the reaction structure and the second turbine hub.

The other modification in Figure 19 is that circumferentially spaced screws 265 provide the drive connection between the mating parts 264 and 273, respectively, of the first turbine member 260 and the second turbine memher. 268. This departure firom Figure 1 is largely a matter of preference and option.

' Figure 20 illustrates an embodiment having the same procession of rows of blades in the fluid recirculatingpath as shown in Figure 1; but in Figure 20, the reaction structure, interposed between and rotationally secured to the first stator core 383 and the second stator core 389, is an annular web 621 conjoining the first stator member and the second stator member. As shown for exemplification, this web is cast integrally with the first and second stator members. This replaces the one-way device 21 of Figure 1 as a matter of simplicity. To moderate the deficiencies relative to characteristics of Figure 1, the speed difierential between the first and second stator members, as shown in Figure 5, would be reduced by modification of the blades of these members and at least the adjacent members, so that the first and second stator members would tend to free-whirl with similar speeds. These changes should include a revision of design radii. Although the characteristics are somewhat deficient relative' to those of Figure 1, the simplicity is very desirable. Considering other improvements being made, such as for blade contours, it is reasonable to expect characteristics, eventually, for this construction which are comparable to those now shown for Figure 1.

Figure 21 somewhat diagrammatically illustrates an the second and third stator members, 86 and 92 respectively, of Figure 1. In sequencefrom the entrance of the pump member in the direction of fluid circulation, the members are: the pump member 450, the first turbine member 460, the first stator member 480, the second turbine member 468, the second stator member 492, and the third turbine member 47'4. A one-way device 421, interposed between the first stator core 483 and the second stator core 495, prevents backward but permits forward rotation of the first stator member 480 relative to the second stator member 492. The operation of this combination is similar to that :of Figure 1, considered without stator member 86. In consideration of this omission, a general revision of blade angles with some modifications of radii is required to comply with the resultant rate of fluid circulation.

This combination is more simple and may be made axially shorter than that of Figure 1. Characteristically this combination gives a high stall torque ratio, but a reduced range of torque conversion, if high etficiency at the coupling point is considered a prime requisite. The utility of this combination tends to be for applications requiring a high stall torque ratio, and using a low speed power source, and consequently, a short speed'range of torque conversion. On the contrary, there are several well known automotive torque converters which have one stator member, the blades of which are positioned in the inner half of the fluid recirculating path. This combination in Figure 21 is far superior to those particular torque converters. Inherently, the first stator member, being positioned in the outer half of the fluid path, gives a high stall torque ratio, and permits the second stator member in the inner half of the fluid path to be featured for higher elficiency at the coupling point, and/ or, a wider speed range of torque conversion. Also, the final turbine member makes its unique contribution to efficiency and power transmitter effectiveness, by reducing shock head losses at the pump member entrance, and by providing a humpbacked input speed curve. Figure 22 is a diagrammatic illustration of an embodiment differing from that of Figure 1, in that, the first stator member and its one-way device 21 is omitted, and the first and second turbine members 60 and 68 are formed as one, being the first turbine member 568. In sequence from the entrance of the pump member in the direction of fluid circulation, the members are: the pump member 550, the first turbine member 568, the first stator member 586, the second stator member 592, and the second turbine member 574. Interposed between the first turbine member and the second turbine member, is a one-v way device 520, enabling the second turbine member to contribute torque to the output shaft, but only in the forward direction-the first turbine member and its hub element 531 serving as .a drive structure for the second turbine member. The operation of this combination is similar to that of Figure 1, considered without stator member '80. Such a change, of course, necessitates a general revision of blade angles and radii, in confideration of different fluid circulation. V

This combination illustrated in Figure 22 is quite obviously simpler than that in Figure l. characteristically compared to the combination in Figure 1, this combination naturally has a lower stall torque ratio; and generally would be made with a lower" efi'iciency at the coupling converters-at least, these are the only torque converters used for general driving without either an automatic There are 21 change gearing or a lock-up clutch for cruising, or'both. Compared to these torque converters, thecombination in Figure 22 is a decided improvement relative to efliciency and to power transmitter efiectiveness, by virtue of the unique influence of the final turbine member which more effectively reduces shock head losses and provides the humpbacked input speed curve.

Figure 23 diagrammatically illustrates a very simple embodiment using only one stator member, the blades of which are positioned in the inner half of the fluid recirculating path. he members, named in se uence from the entrance of the pump member in the direction of fluid circulation are: the pump member 650, the first turbine member 668, the stator member 692, and the second turbine member 674. The first turbine member has a hub element (531 keyed to output shaft 634 interposed between the first turbine core elements 666 and the second turbine core 677 is a one-way device 62%, enabling the second turbine member to contribute torque to the output shaft, but only in the forward direction. A one-Way device 622 is interposed between the stationary reaction shaft 612 and the stator shell 694, enabling the stator member to transmit torque to the reaction shaft but only in the backward direction. 1

There are several well known automotive torque converters which have a comparable stator arrangement. This arrangement severely hampers stall torque ratio, coupling point efficiency, and speed range of torque conversion; consequently, ali of these automotive installations employ for general driving, either an automatic change gearing or a lock-up clutch for cruising, or both. Relative to these automotive torque converters, the combination in Figure 23 is far superior in efiiciency and in power transmitter effectiveness, due to the unique influence of the final turbine member which reduces shock head losses and provides the humpbacked form of input speed curve.

in any of the embodiments disclosed, the final stator member could be rotationally secured relative to the stationary housing, instead of being one-way acting by virtue of being mounted through a one-way device. Then a torque division phase, commonly referred to as over-drive, would supplant the coupling phase of operation. An arrangement with this particular feature is disclosed by Heppner Patent 2,216,411.

In the discussion of the embodiment illustrated in Figure 1, it was shown that the stator member positioned in the outer half of the fluid recirculating path relieved the stator member positioned in the inner half of the fluid recirculating path of much of the stall reaction requirements for which it is physically at a disadvantage; thus, permitting the inner stator member to be constructed with a form conducive of high efiiciency in the coupling point regionv Following similar reasoning, another stator member may be provided at about the average radius of the fluid recirculating path, in an interrupted space of a turbine member, such as, the second turbine member 68 in Figure 1. This would relieve the inner stator of much of the reaction requirements midway in the torque conversion range; hence, the inner stator could be further modified for higher efliciency in the coupling point region, or for a larger speed range of torque conversion as required for a very high speed power source.

Considering high efliciency in the coupling point region a prime requisite, the nature of the stall torque ratio, and the available speed range of torque conversion, for a particular hydrodynamic torque converter is indicated by the features of its reaction arrangement-relative to a transmission with selective gearing: a stator member in the outer portion of the fluid path, simulates a low gear ratio;

a stator member in the irmer portion of the fluid path,

resembles an intermediate gear ratio; and, the fluid coupling phase of operation replaces the clutched through drive. The trend is towards more extensive torque converter operation. To properly replace a mechanical gear- 22 ing ratio, it is logical that a member, characteristically comparable, should be incorporated in the torque converter.

Digest entrance of a pump member; specifically, to vectorially reducing the moment of momentum and the circumferential velocity of the circulating fluid in an early phase, or phases, of operation, but without appreciable counterinfluences in subsequent phases on these properties of the circulating fluid-thereby, increasing the efliciency of the torque converter, and permitting the. power source more freedom to develop power. The mode of physical attainment is a turbine member interposed between the exit of a stator member and the entrance of a pump member, characterized further, by being approximately one-way acting relative to the circumferential velocity of the circulating fluid; thereby, being capable of vectorially reducing the moment of momentum of the circulating fluid and to transmit the change of moment of momentumas torque to the torque converter output shaft, but ineffective to vectorially increase the moment of momentum of the circulating fluid.

So far as I am aware, I am the first to have this conception: or to provide in a hydrodynamic torque converter a bladed member so characterized; or to devise in hydrodynamic torque converters, combinatious of bladed members having various pump, turbine, and stator members correlated and combined with a member so characterized. This invention creates for hydrodynamic torque converters a new class of combinations of bladed members which are physically and characteristically novel, unique, and superior. Hence, I claim this invention generically with essential structural definition to properly characterize and distinguish it, and with supplementary claims further defining form, structure, and/ or features.

Also, I claim the subcombi'nation comprising the characterized turbine member, and with supplementary claims further defining form, structure, and/or features.

Furthermore, I claim plural species with supplementary claims further defining form, structure, and/or features.

As has been thoroughly emphasized, the inventions hereof pertain to improvements in the hydrodynamic transmission of power, during which, the rate of fluid circulation of a combination of members varies with the phase of operation and the power transmitted, but is maintained in the same general direction with respect to the procession of members in the toroidal circuit; and that direction is referred to as the direction of fluid circulation, or according to SAE recommendations, the fluid flow direction.

Also, in accordance with the aforestated SAE recommendations, the terms, first, second, third, and final, are used in the foregoing descriptions and in the appended claims to indicate the sequence of the particular character of member in the fluid flow direction in the recirculating path, referred to as the circuit, starting at the entrance of the first pump member.

Accordingly, a preceding member relative to a specified member means a member which is situated in the fluid circuit ahead of that specified member, that is, is situated from the specified member in the direction counter to the fluid flow direction; and a subsequent or following member relative to a specified member means a member which is situated in the fluid circuit from the specified member in the same direction as that of the fluid flow.

The terms, juxtaposed, interposed, and adjacen are used in the claims in reference to the positioning of bladed-members to indicate sequential position inthe and members is confined to references to the bladedmembers. To eliminate unessential words in the claims, the word member is usually omitted where a specific character of member is recited. Accordingly, as used in V the claims: pump means a pump member; turbine," a

turbine member; and stator, a stator member.

In conformity with general practice, the phases of operation for the foregoing disclosures are numbered sequentially fom stall to the coupling point, the operation thereafter being the coupling phase. Accordingly, in reference to a portion of the torque conversion range of operation, an early phase means a phase of operation in the first half of that torque conversion range which starts at stall; and a late phase of torque conversion means a phase of operation in the second half of that torque conversion range which terminates at the coupling point.

It is, of course, understood that the present invention is not limited to the particular forms and structures shown in the drawings, or otherwise revealed, for disclosure and explanatory purposes, but also embraces modifications within the scope of the appended claims.

I claim:

1. In a hydrodynamic torque converter drive having pump, stator, and turbine bladed-members arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: at least one pump, and means to connect each pump of said combination to an input power structure; at least one stator, and reaction structure means to associate each stator of saidcombination with a stationary support structure to therewith render each said stator firm against backward rotation; a plurality of turbines, including a specially situated turbine and an array of blades thereof, said specially situated turbine relative to said stator and said pump members being interposed between a stator exit thereof and a pump entrance thereof; driven structure means to associate said turbines with an output power shaft to therewith afford, for each of said turbines, restraint of forward rotation for the conversion and transmission of energy to said output shaft, said driven structure means pertinent to said specially situated turbine being thus operative in an early phase of the torque conversion range to enable said blades of said specially situated turbine to vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said specially situated turbine operative in a late phase of the torque conversion range to render said blades of said specially situated turbine backwa-rdly yieldable to circulating fluid and thus ineffective totvectorially increase the moment of momentum thereof while another of said plurality of turbines remains effective to vectorially reduce the moment of momentum of said fluid. I

2. In a hydrodynamic torque converter drive having pump, stator, and turbine bladed-members arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a pump situated with its entrance in the inner half and its exit in the outer .half of said circuit, and means to connect said pump to an input power structure; at least one stator, including a final stator situated in said circuit with an interrupted space between its exit and said pump entrance, and'reaction structure means to associate each stator of said combination with a stationary support structure to therewith render each said stator firm against backward rotation; a plurality of turbines, including a first turbine situated in said circuit with its entrance adjacent to said pump exit, and a final turbine having an array of blades interposed between said final stator exit and said pump entrance; driven structure means to associate said turbines with an output power shaft to therewith afford, for each ofsaid turbines, restraint of forward rotation for the conversion and transmission of energy to said output shaft, said driven structure means pertinent to said. final turbine being thus opera-.

tive in an early phase of the torque conversion rangeto enable said final turbine blades to vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said final turbine opera.-. tive in a late phase of the torque conversion range to render said final turbine blades backwardly yieldable:

to circulating fluid and thus ineffective to vectorially increase the moment of momentum thereof while an: other of said plurality of turbines remains effective to vectorially reduce the moment of momentum of said. fluid.

3. The combination defined in claim 2 in which said restrictive influence means includes means sensitive and responsive to backward impression of said circulating fluid on said final turbine blades to cause said backward yielding thereof.

4. The combination defined in claim 2 in which said restrictive influence means and said driven structure means pertinent to said final turbine include a one-way device interposed in said driven structure means and operative therewith to render said final turbine blades collectively one-way acting, capable ofvectorially reducing but ineffective for vectorially increasing the moment of momentum of circulating fluid.

5. The combination defined in claim 2 in which said restrictive influence means and said driven structure means pertinent to said final turbine include a driven element extending from a core element of said final turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said final turbine relative to said first turbine.

6. The combination defined in claim 2 in which: said restrictive influence means and said driven structure means pertinent to said final turbine include a driven element extending from a core element of said final turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said final turbine relative to said first turbine; and, the features of said final tur bine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

'7. The combination defined in claim 2 in which said reaction structure means includes one-way device means to permit forward rotation operative to render each stator of said combination ineffective to vectorially reduce the moment of momentum of circulating fluid.

8. The combination defined in claim 2 in which: said reaction structure means includes one-way device means to permit forward rotation operative to render each stator of said combination ineffective to vectorially reduce the moment of momentum of circulating fluid; and, the features of said plurality of turbines include the relationship of the design radius at the exit of said final turbine being smaller than the design radius at the exit of the turbine which, relative to said final turbine, is the nearest preceding turbine in said circuit.

9.. The combination defined in claim 2 in which said restrictive influence means and said driven structure means pertinent to said final turbine include a clutching mechanism having opposing elements thereof interposed in drive series relationship in said driven structure means, and having clutching control means operative to effect and maintain, approximate rotational unisonance of said opposing elements when thereby said final turbine transmits considerable energy to said output power shaft, and approximate rotational freedom between said opposing elements when otherwise said final turbine would ex? tract considerable energy from said output power shaft 10. The combination defined in claim 9 in which said clutching control means includes wedging elements disposed and operative between said opposing elements to prevent relative rotation therebetween in one direction and to permit relative rotation therebeween in the opposite direction.

11. In a hydrodynamic torque converter drive having bladed-members, at least one pump, at least one stator, and a plurality of turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a turbine and an array of blades thereof situated in said circuit for the transition of circulating fiuid, and for the conversion of properties thereof, from a stator exit to a pump entrance; driven structure means to associate said turbine with an output power shaft to therewith restrain forward rotation of said turbine in an early phase of the torque converter range, and thus to enable said turbine blades to vectorially reduce the moment of momentum of said circulating fluid; and, restrictive influence means operative in a late phase of the torque conversion range to render said turbine blades backwardly yieldable to said circulating fluid and thus inefiective to vectorially increase the moment of momentum thereof while another of said plurality of turbines remains eflective to vectorially reduce the moment of momentum of said fluid.

12. The combination defined in claim 11 in which said restrictive influence means includes means sensitive and responsive to backward impression of said circulating fluid on said turbine blades to cause said backward yielding thereof.

13. In a hydrodynamic torque converter drive having bladed-members, at least one pump, at least one stator, and a plurality of turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a turbine and an array of blades thereof situated in said circuit for the transition of circulating fluid, and for the conversion of properties thereof, from a stator exit to a pump entrance; driven structure means to associate said turbine with an output power shaft for the restraint of forward rotation of said turbine; and, a one-way device interposed in said driven structure means and operative therewith to render said turbine blades collectively one-way acting, capable of vectorially reducing but inefiective for vectorially increasing the moment of momentum of fluid circulating in said circuit while another of said plurality of turbines remains effective to vectorially reduce the moment of momentum of said fluid.

14. The combination defined in claim 13 in which the features of said turbine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

15. In a hydrodynamic torque converter drive having bladed-members, at least one pump, at least one stator, and a plurality of turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a turbine and an array of blades thereof situated in said circuit for the transition of circulating fluid, and for the conversion of properties thereof, from a stator exit to a pump entrance; driven structure means to associate said turbine with an output power shaft for the transmission of energy thereto; and, a clutching mechanism having opposing elements thereof interposed in drive series relationship in said driven structure means, and having clutching control means operative to efiect and maintain, during the transmission of power by said hydrodynamic drive to said output power shaft, approximate rotational unisonance of said opposing elements when thereby said turbine transmits considerable energy to said output power shaft, and approximate rotational freedom between said opposing elements when otherwise said turbine would extract considerable energy from said output power shaft while another of said plurality of turbines remains elfective to 26 vectorially reduce the moment of momentum of said fluid.

16. The combination defined in claim 15 in which said clutching control means includes wedging elements disposed and operative between said opposing elements to prevent relative rotation therebetween in one direction and to permit relative rotation therebetween in the opposite direction.

17. In a hydrodynamic torque converter drive having bladed-members, one pump, three stators, and three tut-- bines, arranged in spaced relationship in a toroidal circuitfor fluid recirculation, the combination comprising: a pump situated with its entrance in the inner half and its exit in the outer half of said circuit, and means to connect said pump to an input power structure; a first stator situated in the outer half of said circuit with an interrupted space between its entrance and said pump exit; a second stator situated in the inner half of said circuit with two interrupted spaces between its exit and said pump entrance; a third stator situated in the inner half of said circuit with its entrance adjacent to said second stator exit; reaction structure means to associate said stators with a stationary support structure to therewith render each of said stators firm against backward rotation; a first turbine interposed between said pump exit and said first stator entrance; a second turbine situated with its entrance adjacent to the exit of said first stator and its exit adjacent to the entrance of said second. stator; a third turbine having an array of blades interposed between the exit of said third stator and said pump entrance; driven structure means to associate said turbines with an output power shaft to therewith afford, for each of said turbines, restraint of forward rotation for the conversion and transmission of energy to said output shaft, said driven structure means pertinent to said third turbine being thus operative in an early phase of the torque conversion range to enable said third turbine blades to vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said third turbine operative in a late phase of the torque conversion range to render said third turbine blades backwardly yieldable to circulating fluid and thus ineffective to vectorially increase the moment of momentum thereof while said second turbine remains efiective to vectorially reduce the moment of momentum of said fluid.

18. The combination defined in claim 17 in which said restrictive influence means and said driven structure means pertinent to said third turbine include a one-way 'device interposed in said driven structure means and operative therewith to render said third turbine blades collectively one-way acting, capable of vectorially re ducing but ineffective for vectorially increasing the moment of momentum of circulating fluid.

19. The combination defined in claim 17 in which said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third turbine relative to said first turbine.

20. The combination defined in claim 17 in which: said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third turbine relative to said first turbine; and, the features of said third turbine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

'21. The combination defined in claim 17 in whichsaid reaction structure means includes one-way device means to permit forward rotation operative to render each one of said stators ineffective to vectorially-reduce the moment of momentum of circulating fluid.

22. The combination defined in claim 17 in which said reaction structure means includes one-way device, means to permit forward rotation operative to render each one of said stators ineflective to vectorially reduce the moment of momentum of circulating fluid; and, said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third turbine relative to said first turbine.

23. The combination defined in claim 17 in which:

said reaction structure means includes one-way device means to permit forward rotation operative to render each one of said stators inefl'ective to vectorially reduce the moment of momentum of circulating fluid; and, the features of said second and third turbines include the relationship of the design radius at the exit of said third 4 turbine being smaller than the design radius at the exit of said second turbine.

24. The combination defined in claim 17 in which said reaction structure means includes: a reaction shaft and a one-way device arranged to connect said third stator with said stationary support structure and to therewith prevent backward rotation and permit forward rotation of said third stator; a one-way device adapted to prevent backward rotation and to permit forward rotation of said second stator relative to said reaction shaft; and, a core situated one-way device adapted to prevent backward rotation and to permit forward rotation of said first stator relative to one of said stators situated in the inner half of said circuit.

25. The combination defined in claim 17 in which said reaction structure means includes: a reaction shaft and a one-way device arranged to connect said third stator with said stationary support structure and to therewith prevent backward rotation and permit forward rotation of said third stator; a one-way device adapted to prevent backward rotation and to permit forward rotation of said second stator relative to said reaction shaft; and, a core conjunctive element to rotationally secure said first stator to said second stator.

26. In a hydrodynamic torque converter drive having bladed-members, one pump, two stators, and three turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a pump situated with its entrance in the inner half and its exit in the outer half of said circuit, and means to connected said pump to an input power structure; a first stator situated in the outer half of said circuit with an interrupted space between its entrance and said pump exit; a second stator situated in the inner half of said circuit with an interrupted space between its exit and said pump entrance; reaction structure means to associate said stators with a stationary support structure to therewith render each of said stators firm against backward'rotation; a first turbine interposed between said pump exit and said first stator entrance; a second turbine situated with its entrance adjacent to the exit of said first stator andits exit adjacent to the entrance of said second stator; a third turbine having an array of blades interposed between said second stator exit and said pump entrance; driven structure means to associate said turbines with an output power shaft to therewith afiord, for each of said turbines, restraint of forward rotation for the conversion and transmission of energy to'said output shaft, said driven structure means pertinent to said third turbine being thus operative in an early phase of the torque conversion range to enable said third turbine blades to-vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said third turbine operative in a late phase of the torque conversion range to render said third turbine blades backwardiy yieldable to circulating fluid and thus ineffective to vectorially increase the mo-' ment-of momentum thereof while said second turbine remains effective to vectorially reduce the moment of momentum of said fluid.

27. The combination defined in claim 26 in which said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third turbine relative to said first turbine.

28. The combination defined in claim 26 in which: said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third turbine relative to said first turbine; and, the features of said third turbine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

29. The combination defined in claim 26 in which said reaction structure means includes one-way device means to permit forward rotation operative to render each one ofsaid stators ineffective to vectorially reduce the moment of momentum of circulating fluid.

30. The combination defined in claim 26. in which: said reaction structure means includes one-way device means to permit forward rotation operative to render each one of said stators inefiective to vectorially reduce the moment of momentum of circulating fluid; and, said restrictive influence means and said driven structure means pertinent to said third turbine include a driven element extending from a core element of said third turbine to -a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said third tur-, bine relative to said first turbine.

31. Thecombination defined in claim .26 in. which said reaction structure means includes: a reactionshaft and a one-way device arranged to connect'said second stator with said stationary support structure and to therewith prevent backward rotation and permit forward rotation of said second stator; and, a core situated one- Way device adapted to prevent backward rotation and to permit forward rotation of said first stator relative to said second stator.

32. In a hydrodynamic torque converter drive having bladed-members, one pump, two stators, and two turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a. pump situated with its entrance in the innerhalf and its exit in the outer half of said circuit, and means to connect said pump to an input power structure; a first stator situ-.

ated in the inner half of said circuit with two interrupted spaces between its exit and said pump entrance; a second stator situated with its entrance adjacent to said first stator exit; reaction structure means to associate said stators with a stationary support structure to therewith render each one of said stators firm against backward rotation; at first turbine situated with its entrance adjacent to said pump exit and its exit adjacent to the entrance of said first stator; a second turbine having an array of blades interposed between the exit of said sec--' ond stator and said pump entrance; driven structure means to associate said turbines with an output power shaft to therewith afford, for each of said turbines, restraint of forward rotation for the conversion and the transmission of energy to said output shaft, said driven structure means pertinent to said second turbine being thus operative in an early phase of the torque conversion range to enable said second turbine blades to vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said second turbine operative in a late phase of the torque conversion range to render said second turbine blades backwardly yieldable to circulating fluid and thus ineffective to vectorially increase the moment of momentum thereof while said first turbine remains efiective to vectorially reduce the moment of momentum of said fluid.

33. The combination defined in claim 32 in which said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine.

34. The combination defined in claim 32 in which: said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine; and, the features of said second turbine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

35. The combination defined in claim 32 in which said reaction structure means includes one-way device means to permit forward rotation operative to render each one of said stators ineffective to vectorially reduce the moment of momentum of circulating fluid.

36. The combination defined in claim 32 in which: said reaction structure means includes one-way device means to permit forward rotation operative to render each one of said stators ineffective to vectorially reduce the moment of momentum of circulating fluid; and, said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine.

37. The combination defined in claim 32 in which said reaction structure means includes: a reaction shaft and a one-Way device arranged to connect said second stator with said stationary support structure and to therewith prevent backward rotation and permit forward rotation of said second stator; and, a one-way device adapted to prevent backward rotation and to permit forward rotation of said first stator relative to said reaction shaft.

38. In a hydrodynamic torque converter drive having bladed-members, one pump, one stator, and two turbines, arranged in spaced relationship in a toroidal circuit for fluid recirculation, the combination comprising: a pump situated with its entrance in the inner half and its exit in the outer half of said circuit, and means to connect said pump to an input power structure; a stator situated in the inner half of said circuit with an interrupted space between its exit and said pump entrance, and reaction structure means to associate said stator with a stationary support structure to therewith render said stator firm against backward rotation; a first turbine situated with its entrance adjacent to said pump exit and its exit adjacent to the entrance of said stator; a second turbine having an array of blades interposed between said stator exit and said pump entrance; driven structure means to associate said turbines with an output power shaft to therewith afiord, for each of said turbines, restraint of forward rotation for the conversion and transmission of energy to said output shaft, said driven structure means pertinent to said second turbine being thus operative in an early phase of the torque conversion range to enable said second turbine blades to vectorially reduce the moment of momentum of circulating fluid; and, restrictive influence means for said second turbine operative in a late phase of the torque conversion range to render said second turbine blades backwardly yieldable to circulating fluid and thus inefiective to vectorially increase the moment of momentum thereof while said first turbine remains eflective to vectorially reduce the moment of momentum of said fluid.

39. The combination defined in claim 38 in which said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine.

40. The combination defined in claim 38 in which: said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-Way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine; and, the features of said second turbine include the relationship of the design radius at its exit being larger than the design radius at its entrance.

41. The combination defined in claim 38 in which said reaction structure means includes one-way device means to permit forward rotation operative to render said stator ineffective to vectorially reduce the moment of momentum of circulating fluid.

42. The combination defined in claim 38 in which: said reaction structure means includes one-way device means to permit forward rotation operative to render said stator ineffective to vectorially reduce the moment of momentum of circulating fluid; and, said restrictive influence means and said driven structure means pertinent to said second turbine include a driven element extending from a core element of said second turbine to a core element of said first turbine, said driven element including a one-way device interposed therein and operative therewith to permit backward rotation and to prevent forward rotation of said second turbine relative to said first turbine.

43. The combination defined in claim 38 in which said reaction structure means includes a reaction shaft and a one-way device arranged to connect said stator with said stationary support structure and to therewith prevent backward rotation and permit forword rotation of said stator.

References Cited in the file of this patent UNITED STATES PATENTS 1,760,480 Coats May 27, 1930 1,953,458 Bauer et al. Apr. 23, 1934 1,965,518 Wilson July 3, 1934 2,152,113 Van Lammerin Mar. 28, 1939 2,173,604 Dodge Sept. 19, 1939 2,190,830 Dodge Feb. 20, 1940 (Other references on following page) 

